FIELD OF THE INVENTION
The invention relates to an antitheft system for a motor vehicle. In particular, the invention relates to a lock system by which an immobilizer of the motor vehicle is enabled.
An antitheft system which is known from U.S. Pat. No. 5,053,774 has a portable transponder that receives an inquiry code signal from a stationary transceiver. After the inquiry code signal has been received, a reply code signal is sent back to the transceiver. Energy which is used to trigger the reply code signal is also transmitted in the inquiry code signal. The energy is temporarily stored in an accumulator. If sufficient energy is present in the accumulator, the code signal is triggered.
If the transponder and the transceiver are poorly coupled to one another, it may, under certain circumstances, be a very long time until the accumulator is charged.